POS0968 CESAREAN SECTION IN WOMEN WITH SPONDYLOARTHRITIS AND PSORIATIC ARTHRITIS

Background

There is sparse documentation on pregnancy outcomes in women with spondyloarthritis (SpA) and psoriatic arthritis (PsA). Data on disease activity is often lacking, preventing the direct investigation of the effect of inflammation on pregnancy outcomes. A cesarean section (CS) implies a higher risk for the mother than vaginal delivery. It delays mobilization after birth necessary to counteract inflammatory pain and stiffness as well as the (re)start of disease modifying medication.

Objectives

To explore the possible association of disease activity (inflammation) and occurrence of cesarean section in women with SpA and PsA.

Methods

Data from the Medical Birth Registry of Norway (MBRN) were linked with data from RevNatus, a nationwide observational register recruiting women with inflammatory rheumatic diseases. Singleton births in women with SpA and PsA included in RevNatus 2010 to 2019 were cases. All other singleton births registered in MBRN during this time served as population controls.

Results

CS occurred more frequently in both SpA (21.9%) and PsA (29.4%) compared to population controls (15.6%), with even higher frequencies in active SpA (23.5%) and active PsA (30.1%). Women with SpA had higher risk for elective CS (risk difference 4.1%, 95% CI 1.4% to 7.9%, p=0.002), while women with PsA had higher risk for emergency CS (risk difference 9.8%, 95% CI 3.8% to 17.6%, p<0.001) as compared to population controls.

Conclusion

Women with SpA and PsA had increased odds for elective and emergency CS, respectively. Further analysis will explore the role of active inflammation.

References

[1]Mørk, S et al. Spondyloarthritis and Outcomes in Pregnancy and Labor: A Nationwide Register-Based Cohort Study. Arthritis Care Res (Hoboken). 2021 Feb;73(2):282-288

Table 1.

Characteristics of population controls, total patient groups and patient active disease groups, reported as n (%) unless specified as mean (SD)

CharacteristicPopulation controlsSpondylo arthritis SpASpA active BASDAI≥4Psoriatic Arthritis PsAPsA active DAS28>2.6Number singleton births 2010 - 2019575 79831911512629Maternal age (years), mean (SD)30.6 (5.1)31.7(4.3)131.8 (4.3)32.0 (4.7)431.8 (4.4)<35460 720 (80.0)242 (77.6)89 (78.1)87 (71.9)20 (74.1)≥35115 077(20.0)70 (22.4)25 (21.9)34 (28.1)7 (25.9)ParityNo children244 354 (42.4)141 (45.2)43 (37.7)48 (39.7)10 (37.0)≥ 1 child331 444 (57.6)171 (54.8)71 (62.3)73 (60.3)17 (63.0)Smoking in pregnancy34 237 (6.7)19 (6.3)10 (9.3)9 (7.1)5 (20.0)BMI first trimester, mean (SD)24.4 (4.8)25.1 (5.0)26.5 (5.8)26.9 (5.6)528.8 (4.9)Cesarean section, CS89 840 (15.6)70 (21.9)227 (23.5)37 (29.4)69 (31.0)Elective32 114 (5.6)31 (9.7)315 (13.0)12 (9.5)2 (6.9)Emergency57 691 (10.0)39 (12.2)12 (10.5)25 (19.9)77 (24.1)Earlier caesarean section55 992 (9.7)32 (10.0)16 (13.9)15 (11.9)3 (10.3)Disease activityInactive 3rd trimna134 (53.8)na67 (69.8)naActive 3rd trimna115 (46.2)11529 (30.2)29

1-7 Group compared to population controls 1p<0.001 2 p=0.002 3 p=0.002 4 p=0.001 5 p<0.001 6 p<0.001 7 p<0.001

Disclosure of Interests

None declared

The impact of levator ani muscle trauma and contraction on recurrence after prolapse surgery

Introduction and hypothesis

The objective was to explore the impact of levator ani muscle (LAM) trauma and pelvic floor contraction on symptoms and anatomy after pelvic organ prolapse (POP) surgery.

Methods

Prospective study including 200 women with symptomatic POP ≥ grade 2 examined 3 months prior to and 6 months after surgery. Prolapse in each compartment was graded using the Pelvic Organ Prolapse Quantification (POP-Q) system, and women answered yes/no to a question about bulge sensation. Pelvic floor muscle contraction was assessed with transperineal ultrasound measuring proportional change in levator hiatal anteroposterior diameter from rest to contraction. LAM trauma was diagnosed using tomographic ultrasound imaging. Statistical analysis was performed using multivariate logistic regression analysis.

Results

A total of 183 women (92%) completed the study. Anatomical recurrence (POP ≥ grade 2) was found in 76 women (42%), and a bulge sensation was reported by 35 (19%). Ninety-two women (50%) had LAM trauma, and this was associated with increased risk of anatomical recurrence (OR 2.1 (95% CI 1.1–4.1), p = 0.022), but not bulge sensation (OR 1.1 (95% CI 0.5–2.4), p = 0.809). We found a reduced risk of bulge sensation for women with absent to weak contraction compared with normal to strong contraction (OR 0.4 (95% CI 0.1–0.9), p = 0.031), but no difference in risk for POP ≥ 2 after surgery (OR 1.5 (95% CI 0.8–2.9), p = 0.223).

Conclusions

Levator ani muscle trauma was associated with increased risk of anatomical failure 6 months after POP surgery. Absent to weak pelvic floor muscle contraction was associated with reduced risk of bulge sensation after surgery.

Vitamin D and stress urinary incontinence in pregnancy: a cross-sectional study

OBJECTIVE

To assess the association between levels of vitamin D and urinary incontinence (UI) in pregnancy.

DESIGN

A cross-sectional study. Secondary analysis of a randomised controlled trial.

SETTING

Two university hospitals in Norway.

POPULATION

A total of 851 healthy, pregnant women >18 years in gestational weeks 18-22 with a singleton live fetus.

METHODS

Data on UI were collected from a questionnaire at inclusion and serum analysis of 25-hydroxy vitamin D (25(OH)D) was performed. Univariable and multivariable logistic regression analyses were applied to study associations between exposure and outcomes.

MAIN OUTCOME MEASURES

Prevalence of self-reported UI, stress (SUI) and urge (UUI) or mixed UI.

RESULTS

In total, 230/851 (27%) of the participants were vitamin D insufficient (25(OH)D <50 nmol/l) and 42% reported to have any UI. Women with 25(OH)D <50 nmol/l were more likely to report any UI (P = 0.03) and SUI (P < 0.01) compared with women with 25(OH)D ≥50 nmol/l. In a univariable logistic regression analysis, serum levels of 25(OH)D <50 nmol/l was associated with increased risk of any UI (odds ratio [OR] 1.5 with 95% CI 1.0-2.1), SUI only (OR 1.7, 95% CI 1.2-2.4), but not mixed UI or UUI only (OR 0.8, 95% CI 0.5-1.5). In a multivariable logistic regression model, serum levels of 25(OH)D <50 nmol/l were associated with a higher risk of experiencing SUI only (OR 1.5, 95% CI 1.1-2.2).

CONCLUSIONS

Serum 25(OH)D <50 nmol/l was associated with increased risk of any UI, and SUI in particular.

TWEETABLE ABSTRACT

Low levels of vitamin D are associated with increased risk of urinary incontinence in pregnancy.

Effect of preoperative pelvic floor muscle training on pelvic floor muscle contraction and symptomatic and anatomical pelvic organ prolapse after surgery: randomized controlled trial

OBJECTIVES

To evaluate the effect of preoperative pelvic floor muscle training (PFMT) on pelvic floor muscle (PFM) contraction, symptoms of pelvic organ prolapse (POP) and anatomical POP, 6 months after prolapse surgery, and to assess the overall changes in PFM contraction, POP symptoms and pelvic organ descent after surgery.

METHODS

This was a randomized controlled trial of 159 women with symptomatic POP, Stage 2 or higher, scheduled for surgery. Participants were randomized to intervention including daily PFMT from inclusion to surgery (n = 81) or no intervention (controls; n = 78). Participants were examined at inclusion, on the day of surgery and 6 months after surgery. PFM contraction was assessed by: vaginal palpation using the Modified Oxford scale (MOS; 0-5); transperineal ultrasound, measuring the percentage change in levator hiatal anteroposterior diameter (APD) from rest to maximum PFM contraction; vaginal manometry; and surface electromyography (EMG). POP distance from the hymen in the compartment with the most dominant prolapse and organ descent in the anterior, central and posterior compartments were measured on maximum Valsalva maneuver. POP symptoms were assessed based on the sensation of vaginal bulge, which was graded using a visual analog scale (VAS; 0-100 mm). Linear mixed models were used to assess the effect of PFMT on outcome variables.

RESULTS

Of the 159 women randomized, 151 completed the study, comprising 75 in the intervention and 76 in the control group. Mean waiting time for surgery was 22 ± 9.7 weeks and follow-up was performed on average 28 ± 7.8 weeks after surgery. Postoperatively, no difference was found between the intervention and control groups with respect to PFM contraction assessed by vaginal palpation (MOS, 2.4 vs 2.2; P = 0.101), manometry (19.4 vs 19.7 cmH₂ O; P = 0.793), surface EMG (33.5 vs 33.1 mV; P = 0.815) and ultrasound (change in hiatal APD, 20.9% vs 19.3%; P = 0.211). Furthermore, no difference between groups was found for sensation of vaginal bulge (VAS, 7.4 vs 6.0 mm; P = 0.598), POP distance from the hymen in the dominant prolapse compartment (-1.8 vs -2.0 cm; P = 0.556) and sonographic descent of the bladder (0.5 vs 0.8 cm; P = 0.058), cervix (-1.3 vs -1.1 cm; P = 0.569) and rectal ampulla (0.3 vs 0.4 cm; P = 0.434). In all patients, compared with findings at initial examination, muscle contraction improved after surgery, as assessed by palpation (MOS, 2.1 vs 2.3; P = 0.007) and ultrasound (change in hiatal APD, 17.5% vs 20.1%; P = 0.001), and sensation of vaginal bulge was reduced (VAS, 57.6 vs 6.7 mm; P < 0.001). In addition, compared with the baseline examination, POP distance from the hymen in the dominant prolapse compartment (1.9 vs -1.9 cm; P < 0.001) and sonographic descent of the bladder (1.3 vs 0.6 cm; P < 0.001), cervix (0.0 vs -1.2 cm; P < 0.001) and rectal ampulla (0.9 vs 0.4 cm; P = 0.001) were reduced.

CONCLUSIONS

We found no effect of preoperative PFMT on PFM contraction, POP symptoms or anatomical prolapse after surgery. In all patients, PFM contraction and POP symptoms were improved at the 6-month follow-up, most likely due to the anatomical correction of POP. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Ultrasound assessment of pelvic floor muscle contraction: reliability and development of an ultrasound-based contraction scale

OBJECTIVES

To determine intra- and interrater reliability and agreement for ultrasound measurements of pelvic floor muscle contraction and to assess the correlation between ultrasound and vaginal palpation. We also aimed to develop an ultrasound scale for assessment of pelvic floor muscle contraction.

METHODS

This was a cross-sectional study of 195 women scheduled for stress urinary incontinence (n = 65) or prolapse (n = 65) surgery or who were primigravid (n = 65). Pelvic floor muscle contraction was assessed by vaginal palpation using the Modified Oxford Scale (MOS) and by two- and three-dimensional (2D/3D) transperineal ultrasound. Proportional change in 2D and 3D levator hiatal anteroposterior (AP) diameter and 3D levator hiatal area between rest and contraction were used as measures of pelvic floor muscle contraction. One rater repeated all ultrasound measurements on stored volumes, which were used for intrarater reliability and agreement analysis, and three independent raters analyzed 60 ultrasound volumes for interrater reliability and agreement analysis. Reliability was assessed using the intraclass correlation coefficient (ICC) and agreement using Bland-Altman analysis. Tomographic ultrasound was used to identify women with major levator injury. Spearman's rank correlation coefficient (r_S ) was used to assess the correlation between ultrasound measurements of pelvic floor muscle contraction and MOS score. The proportion of women allocated to each category of muscle contraction (absent, weak, moderate or strong) by palpation was used to determine the cut-offs for the ultrasound scale.

RESULTS

Intrarater ICC was 0.81 (95% CI, 0.74-0.85) for proportional change in 2D levator hiatal AP diameter. Interrater ICC was 0.82 (95% CI, 0.72-0.89) for proportional change in 2D AP diameter, 0.80 (95% CI, 0.69-0.88) for proportional change in 3D AP diameter and 0.72 (95% CI, 0.56-0.83) for proportional change in hiatal area. The prevalence of major levator injury was 22.6%. The strength of correlation (r_S ) between ultrasound measurements and MOS score was 0.52 for 2D AP diameter, 0.62 for 3D AP diameter and 0.47 for hiatal area (P < 0.001 for all). On the ultrasound contraction scale, proportional change in 2D levator hiatal AP diameter of < 1% corresponds to absent, 2-14% to weak, 15-29% to normal and > 30% to strong contraction.

CONCLUSIONS

Ultrasound seems to be an objective and reliable method for evaluation of pelvic floor muscle contraction. Proportional change in 2D levator hiatal AP diameter had the highest ICC and moderate correlation with MOS score assessed by vaginal palpation, and we constructed an ultrasound scale for assessment of pelvic floor muscle contraction based on this measure. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Neurodevelopmental outcome in 7-year-old children is not affected by exercise during pregnancy: follow up of a multicentre randomised controlled trial

OBJECTIVE

To investigate whether regular moderate intensity exercise during pregnancy had adverse effect on neurodevelopment of offspring at 7 years of age.

DESIGN

Follow up of a multicentre randomised controlled trial.

SETTING

St Olavs Hospital, Trondheim University Hospital and Stavanger University Hospital, Norway (2007-09).

POPULATION

Women randomised to follow a 12-week structured exercise protocol or standard antenatal care during pregnancy.

METHODS

At 7 years of age, neurodevelopmental outcome was assessed by the parent questionnaire Five-To-Fifteen (FTF), including motor skills, executive functions, perception, memory, language, social skills and possible emotional/behavioural problems.

MAIN OUTCOME MEASURE

Continuous and dichotomised (cut-off 90th centile) FTF scores.

RESULTS

A total of 855 women were randomised to exercise (n = 429) or standard antenatal care (n = 426) during pregnancy. At follow up, 164 (38.2%) children born to mothers in the intervention group and 115 (27.0%) children born to mothers in the control group participated. We found no group differences in FTF scores or in the proportion of children with scores ≥90th centile. Stratified analyses by sex, subgroup analyses of women who adhered to the exercise protocol or sensitivity analyses excluding preterm children and/or children who had been admitted to the neonatal intensive care unit did not change the results.

CONCLUSIONS

In the present randomised controlled trial follow-up study, regular moderate intensity exercise during pregnancy did not have adverse effect on neurodevelopment of offspring at 7 years of age.

TWEETABLE ABSTRACT

Moderate intensity exercise during pregnancy had no adverse effect on neurodevelopment of offspring at 7 years of age.

Descent of fetal head during active pushing: secondary analysis of prospective cohort study investigating ultrasound examination before operative vaginal delivery

OBJECTIVES

To investigate if descent of the fetal head during active pushing is associated with duration of operative vaginal delivery, mode of delivery and neonatal outcome in nulliparous women with prolonged second stage of labor.

METHODS

This was a prospective cohort study of nulliparous women with prolonged second stage of labor, conducted between November 2013 and July 2016 in five European countries. Fetal head descent was measured using transperineal ultrasound. Head-perineum distance (HPD) was measured between contractions and on maximum contraction during active pushing, and the difference between these values (ΔHPD) was calculated. The main outcome was duration of operative vaginal delivery, estimated using survival analysis to calculate hazard ratios (HRs) for vaginal delivery, with values > 1 indicating a shorter duration. HR was adjusted for prepregnancy body mass index, maternal age, induction of labor, augmentation with oxytocin and use of epidural analgesia. Pregnancies were grouped according to ΔHPD quartile, and delivery mode and neonatal outcome were compared between groups.

RESULTS

The study population comprised 204 women. Duration of vacuum extraction was shorter with increasing ΔHPD. Estimated mean duration was 10.0, 9.0, 8.8 and 7.5 min in pregnancies with ΔHPD in the first to fourth quartiles, respectively, and the adjusted HR for vaginal delivery, using increasing ΔHPD as a continuous variable, was 1.04 (95% CI, 1.01-1.08). Mean ΔHPD was 7 mm (range, -10 to 37 mm). ΔHPD was either negative or ≤ 2 mm in the lowest quartile. In this group, 7/50 (14%) pregnancies were delivered by Cesarean section, compared with 8/154 (5%) of those with ΔHPD > 2 mm (P < 0.05). There was no significant association between umbilical artery pH < 7.10 or 5-min Apgar score < 7 and ΔHPD quartile.

CONCLUSION

Minimal or no fetal head descent during active pushing was associated with longer duration of operative vaginal delivery and higher frequency of Cesarean section in nulliparous women with prolonged second stage of labor. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Hysterotomy level at Cesarean section and occurrence of large scar defects: a randomized single-blind trial

OBJECTIVE

To study the association between the level of Cesarean hysterotomy and the presence of large uterine scar defects 6-9 months after delivery.

METHODS

This was a two-center, randomized, single-blind trial of a surgical procedure with masked assessment of the principal outcome under study. Women without a history of Cesarean section (CS) who underwent emergency CS at cervical dilatation ≥ 5 cm were randomized to high or low incision. Hysterotomy was performed 2 cm above and 2 cm below the plica vesicouterina in the high and low incision groups, respectively. Women were examined using saline contrast sonohysterography to assess the appearance of the hysterotomy scar 6-9 months after delivery. The main outcome was presence of a large scar defect, defined as the remaining myometrial thickness over the defect being ≤ 2.5 mm. Secondary outcomes were perinatal outcome, operative complications within 8 weeks after delivery and long-term outcome in a subsequent pregnancy.

RESULTS

Of 122 patients enrolled in the trial, 114 were assessed by ultrasound examination, of whom 55 were randomized to high and 59 to low CS incision. Large scar defects were seen in four (7%) women in the high-incision group and in 24 (41%) in the low-incision group (P < 0.001; odds ratio, 8.7 (95% CI, 2.8-27.4)). There were no differences in operative complications and perinatal outcomes between the two groups. The median follow-up time was 4 years and 7 months, during which 56 (49%) women had a subsequent pregnancy. No significant differences were observed in the rate of complications in subsequent pregnancy and delivery between women who had low and those who had high incision at the index CS.

CONCLUSION

Low Cesarean hysterotomy level in women in advanced labor is associated with higher incidence of large scar defects detected by transvaginal ultrasound examination 6-9 months after delivery. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Association between pelvic floor muscle trauma and contraction in parous women from a general population

OBJECTIVE

To study possible associations between pelvic floor muscle contraction, levator ani muscle (LAM) trauma and/or pelvic organ prolapse (POP) ≥ Stage 2 in parous women recruited from a general population.

METHODS

This was a secondary analysis of data from a cross-sectional study of 608 parous women from a general population examined using the POP quantification system (POP-Q) and three-dimensional/four-dimensional transperineal ultrasound for identification of LAM macrotrauma (avulsion) and microtrauma (distension of levator hiatal area > 75^th percentile on Valsalva maneuver). Muscle contraction was assessed using the modified Oxford scale (MOS), perineometry and ultrasound measurement of proportional change of anteroposterior hiatal diameter and levator hiatal area at rest and on pelvic floor muscle contraction. The Mann-Whitney U-test was used to study associations between pelvic floor muscle contraction, LAM trauma and POP.

RESULTS

Women with macrotrauma (n = 113) had significantly weaker median pelvic floor muscle contraction, as measured using MOS and perineometry, than did women with an intact LAM (n = 493) (contraction strength was 1.5 (range, 0.0-5.0) vs 3.5 (range, 0.0-5.0) on MOS, and vaginal squeeze pressure was 15.0 (range, 0.0-78.0) cmH₂ O vs 28.0 (range, 0.0-129.0) cmH₂ O on perineometry; P < 0.001). This was also demonstrated by ultrasound measurement, with a proportional change in hiatal area of 19.9% (range, 4.1-48.0%) vs 34.0% (range, 0.0-64.0%) (P < 0.001) and proportional change in anteroposterior diameter of 16.2% (range, -5.7 to 42.6%) vs 26.0% (range, -3.4 to 49.4%) (P < 0.001). No statistically significant difference between women with (n = 65), and those without (n = 378), microtrauma was found after excluding women with macrotrauma. Women with POP had weaker muscle contraction than those without; in those with POP-Q ≥ 2 (n = 275) compared with those with POP-Q < 2 (n = 333), muscle contraction strength was 3.0 (range, 0.0-5.0) vs 3.5 (range, 0.0-5.0) on MOS, vaginal squeeze pressure was 21.0 (range, 0.0-98.0) cmH₂ O vs 28.0 (range, 3.0-129.0) cmH₂ O on perineometry, proportional change in hiatal area was 29.6% (range, 0.0-60.9%) vs 33.8% (range, 0.0-64.4%) and proportional change in anteroposterior diameter was 22.8% (range, -5.7 to 49.4%) vs 25.7% (range, -3.4 to 49.4%) (P < 0.001 for all).

CONCLUSIONS

LAM macrotrauma was associated with weaker pelvic floor muscle contraction measured using palpation, perineometry and ultrasound. Women with POP had weaker contraction than did women without POP. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Anal sphincter defects and fecal incontinence 15-24 years after first delivery: a cross-sectional study

OBJECTIVES

To establish the prevalence of external (EAS) and internal (IAS) anal sphincter defects present 15-24 years after childbirth according to mode of delivery, and their association with development of fecal incontinence (FI). The study additionally aimed to compare the proportion of women with obstetric anal sphincter injuries (OASIS) reported at delivery with the proportion of women with sphincter defect detected on ultrasound 15-24 years later.

METHODS

This was a cross-sectional study including 563 women who delivered their first child between 1990 and 1997. Women responded to a validated questionnaire (Pelvic Floor Distress Inventory) in 2013-2014, from which the proportion of women with FI was recorded. Information about OASIS was obtained from the National Birth Registry. Study participants underwent four-dimensional transperineal ultrasound examination. Defect of EAS or IAS of ≥ 30° in at least four of six slices on tomographic ultrasound was considered a significant defect and was recorded. Four study groups were defined based on mode of delivery of the first child. Women who had delivered only by Cesarean section (CS) constituted the CS group. Women in the normal vaginal delivery (NVD) group had NVD of their first child and subsequent deliveries could be NVD or CS. The forceps delivery (FD) group included women who had FD, NVD or CS after FD of their first born. The vacuum delivery (VD) group included women who had VD, NVD or CS after VD of their first born. Multiple logistic regression was used to calculate adjusted odds ratios (aORs) for comparison of prevalence of an EAS defect following different modes of delivery and to test its association with FI. Fisher's exact test was used to calculate crude odds ratios (ORs) for IAS defects.

RESULTS

Defects of EAS and IAS were found after NVD (n = 201) in 10% and 1% of cases, respectively, after FD (n = 144) in 32% and 7% of cases and after VD (n = 120) in 15% and 4% of cases. No defects were found after CS (n = 98). FD was associated with increased risk of EAS defect compared with NVD (aOR = 3.6; 95% CI, 2.0-6.6) and VD (aOR = 3.0; 95% CI, 1.6-5.6) and with increased risk of IAS defect compared with NVD (OR = 7.4; 95% CI, 1.5-70.5). The difference between VD and NVD was not significant for EAS or IAS. FI was reported in 18% of women with an EAS defect, in 29% with an IAS defect and in 8% without a sphincter defect. EAS and IAS defects were associated with increased risk of FI (aOR = 2.5 (95% CI, 1.3-4.9) and OR = 4.2 (95% CI, 1.1-13.5), respectively). Of the ultrasonographic sphincter defects, 80% were not reported as OASIS at first or subsequent deliveries.

CONCLUSIONS

Anal sphincter defects visualized on transperineal ultrasound 15-24 years after first delivery were associated with FD and development of FI. Ultrasound revealed a high proportion of sphincter defects that were not recorded as OASIS at delivery. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Validation of prediction model for successful vaginal birth after Cesarean delivery based on sonographic assessment of hysterotomy scar

OBJECTIVE

To validate a prediction model for successful vaginal birth after Cesarean delivery (VBAC) based on sonographic assessment of the hysterotomy scar, in a Swedish population.

METHODS

Data were collected from a prospective cohort study. We recruited non-pregnant women aged 18-35 years who had undergone one previous low-transverse Cesarean delivery at ≥ 37 gestational weeks and had had no other uterine surgery. Participants who subsequently became pregnant underwent transvaginal ultrasound examination of the Cesarean hysterotomy scar at 11 + 0 to 13 + 6 and at 19 + 0 to 21 + 6 gestational weeks. Thickness of the myometrium at the thinnest part of the scar area was measured. After delivery, information on pregnancy outcome was retrieved from hospital records. Individual probabilities of successful VBAC were calculated using a previously published model. Predicted individual probabilities were divided into deciles. For each decile, observed VBAC rates were calculated. To assess the accuracy of the prediction model, receiver-operating characteristics curves were constructed and the areas under the curves (AUC) were calculated.

RESULTS

Complete sonographic data were available for 120 women. Eighty (67%) women underwent trial of labor after Cesarean delivery (TOLAC) with VBAC occurring in 70 (88%) cases. The scar was visible in all 80 women at the first-trimester scan and in 54 (68%) women at the second-trimester scan. AUC was 0.44 (95% CI, 0.28-0.60) among all women who underwent TOLAC and 0.51 (95% CI, 0.32-0.71) among those with the scar visible sonographically at both ultrasound examinations.

CONCLUSION

The prediction model demonstrated poor accuracy for prediction of successful VBAC in our Swedish population. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Assessment of Cesarean hysterotomy scar before pregnancy and at 11-14 weeks of gestation: a prospective cohort study

OBJECTIVE

To compare the appearance and measurement of Cesarean hysterotomy scar before pregnancy and at 11-14 weeks in a subsequent pregnancy.

METHODS

This was a prospective cohort study of women aged 18-35 years who had one previous Cesarean delivery (CD) at ≥ 37 weeks. Women were examined with saline contrast sonohysterography 6-9 months after CD. A scar defect was defined as large if scar thickness was ≤ 2.5 mm. Women were followed up and those who became pregnant were examined by transvaginal ultrasound at 11-14 weeks. Scar thickness was measured and scars were classified subjectively as a scar with or without a large defect. A receiver-operating characteristics curve was constructed to determine the best cut-off value for scar thickness to define a large scar defect at the 11-14-week scan.

RESULTS

A total of 111 women with a previous CD were scanned in the non-pregnant state and at 11-14 weeks in a subsequent pregnancy. The best cut-off value for scar thickness to define a large scar defect at 11-14 weeks was 2.85 mm, which had 90% sensitivity (18/20), 97% specificity (88/91) and 95% accuracy (106/111). In the non-pregnant state, large scar defects were found in 18 (16%) women and all were confirmed at the 11-14-week scan. In addition, a large defect was found in three women at 11-14 weeks that was not identified in the non-pregnant state.

CONCLUSION

The appearance of the Cesarean hysterotomy scar was similar in the non-pregnant state and at 11-14 weeks in a subsequent pregnancy. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Assessment of pelvic floor muscle contraction with palpation, perineometry and transperineal ultrasound: a cross-sectional study

OBJECTIVE

To study the correlation between palpation, perineometry and transperineal ultrasound for assessment of pelvic floor muscle contraction and to define a contraction scale for ultrasound measurements.

METHODS

This was a cross-sectional study of 608 women examined with palpation of pelvic floor muscle contraction, using the Modified Oxford Scale, and measurement of the vaginal squeeze pressure with a vaginal balloon connected to a fiber-optic microtip transducer (perineometry). Transperineal ultrasound was used for measurements of levator hiatal area and anteroposterior (AP) diameter in the plane of minimal hiatal dimensions, at rest and on contraction. The pelvic floor muscle contraction was expressed as the percentage difference between values at rest and on contraction. Spearman's rank was used to test for correlation between the different methods of assessment.

RESULTS

Significant correlations were found between all assessment methods (P < 0.001). Palpation correlated with perineometry (rs = 0.74) and with proportional change in hiatal area (rs = 0.67) and AP diameter (rs = 0.69) on ultrasound. Perineometry correlated with proportional change in hiatal area (rs = 0.60) and AP diameter (rs = 0.66) on ultrasound. We defined a contraction scale based on the proportional change in AP diameter. In this population, a change in AP diameter of < 7% corresponded to absence of contractions, 7-18% corresponded to weak contractions, 18-35% corresponded to normal contractions and > 35% corresponded to strong contractions.

CONCLUSIONS

We found moderate to strong correlation between ultrasound measurements, palpation and perineometry for assessing pelvic floor muscle contraction. The proportional change in levator hiatal AP diameter was the ultrasound measurement with strongest correlation to palpation and perineometry and formed the basis for the contraction scale for ultrasound measurements. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Assessment of Cesarean hysterotomy scar in non-pregnant women: reliability of transvaginal sonography with and without contrast enhancement

OBJECTIVES

To determine intra- and interobserver reliability of evaluating the appearance and measurement of Cesarean hysterotomy scars using transvaginal ultrasound (TVS), with and without saline contrast sonohysterography (SCSH), in non-pregnant women.

METHODS

Fifty-six women with one previous Cesarean delivery were examined by TVS, with and without contrast enhancement, 6-9 months after the Cesarean delivery. Two observers, blinded to their own and each other's measurements, evaluated the appearance of the hysterotomy scar and measured the myometrial thickness adjacent to the scar or scar defect (MTS). If a scar defect was noted, the remaining myometrial thickness over the defect (RMT) was measured. A scar defect was defined as large if RMT was ≤ 2.2 mm on conventional TVS and ≤ 2.5 mm when SCSH was performed. Intra- and interobserver reliability of conventional TVS and SCSH were assessed.

RESULTS

Intraobserver reliability was good, with intraclass correlation coefficients (ICCs) of ≥ 0.97 for measurements of MTS and RMT on conventional TVS and SCSH. Interobserver ICCs for measurements obtained on SCSH were 0.85 (95% CI, 0.76-0.91) for MTS and 0.96 (95% CI, 0.93-0.98) for RMT, compared with 0.82 (95% CI, 0.72-0.89) for MTS and 0.87 (95% CI, 0.68-0.95) for RMT measured on conventional TVS. The kappa coefficient for measurements obtained on SCSH was 0.92, compared with 0.85 for conventional TVS. Intermethod ICC was 0.86 (95% CI, 0.78-0.92) for measurement of MTS and 0.89 (95% CI, 0.78-0.95) for measurement of RMT, with a kappa coefficient of 0.57.

CONCLUSIONS

Measurement of RMT using SCSH is a reliable method for assessing Cesarean hysterotomy scars in non-pregnant women and can be used in clinical practice. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Prediction of delivery mode by ultrasound-assessed fetal position in nulliparous women with prolonged first stage of labor

OBJECTIVES

To ascertain if fetal head position on transabdominal ultrasound is associated with delivery by Cesarean section in nulliparous women with a prolonged first stage of labor.

METHODS

This was a prospective observational study performed at Stavanger University Hospital, Norway, and Addenbrooke's Hospital, Cambridge, UK, between January 2012 and April 2013. Nulliparous pregnant women with a singleton cephalic presentation at term and prolonged labor had fetal head position assessed by ultrasound. The main outcome was Cesarean section vs vaginal delivery, and secondary outcomes were association of fetal head position with operative vaginal delivery and duration of remaining time in labor.

RESULTS

Fetal head position was assessed successfully by ultrasound examination in 142/150 (95%) women. In total, 19/50 (38%) women with a fetus in the occiput posterior (OP) position were delivered by Cesarean section compared with 16/92 (17%) women with a fetus in a non-OP position (P = 0.01). On multivariable logistic regression analysis, the OP position predicted delivery by Cesarean section with an odds ratio (OR) of 2.9 (95% CI, 1.3-6.7; P = 0.01) and induction of labor with an OR of 2.4 (95% CI, 1.0-5.6; P = 0.05). Fetal head position was not associated with operative vaginal delivery or with remaining time in labor. The agreement between a digital and an ultrasound assessment of OP position was poor (Cohen's kappa = 0.19; P = 0.18).

CONCLUSION

OP fetal head position assessed by transabdominal ultrasound was significantly associated with delivery by Cesarean section.

Forceps delivery is associated with increased risk of pelvic organ prolapse and muscle trauma: a cross-sectional study 16-24 years after first delivery

OBJECTIVES

To study possible associations between mode of delivery and pelvic organ prolapse (POP) and pelvic floor muscle trauma 16-24 years after first delivery and, in particular, to identify differences between forceps and vacuum delivery.

METHODS

This was a cross-sectional study including 608 women who delivered their first child in 1990-1997 and were examined with POP quantification (POP-Q) and pelvic floor ultrasound in 2013-2014. Outcome measures were POP ≥ Stage 2 or previous prolapse surgery, levator avulsion and levator hiatal area on Valsalva. Univariable and multivariable logistic regression analyses and ANCOVA were applied to identify outcome variables associated with mode of delivery.

RESULTS

Comparing forceps to vacuum delivery, the adjusted odds ratios (aOR) were 1.72 (95% CI, 1.06-2.79; P = 0.03) for POP ≥ Stage 2 or previous prolapse surgery and 4.16 (95% CI, 2.28-7.59; P < 0.01) for levator avulsion. Hiatal area on Valsalva was larger, with adjusted mean difference (aMD) of 4.75 cm(2) (95% CI, 2.46-7.03; P < 0.01). Comparing forceps with normal vaginal delivery, the adjusted odds ratio (aOR) was 1.74 (95% CI, 1.12-2.68; P = 0.01) for POP ≥ Stage 2 or surgery and 4.35 (95% CI, 2.56-7.40; P < 0.01) for levator avulsion; hiatal area on Valsalva was larger, with an aMD of 3.84 cm(2) (95% CI, 1.78-5.90; P < 0.01). Comparing Cesarean delivery with normal vaginal delivery, aOR was 0.06 (95% CI, 0.02-0.14; P < 0.01) for POP ≥ Stage 2 or surgery and crude OR was 0.00 (95% CI, 0.00-0.30; P < 0.01) for levator avulsion; hiatal area on Valsalva was smaller, with an aMD of -8.35 cm(2) (95% CI, -10.87 to -5.84; P < 0.01). No differences were found between vacuum and normal vaginal delivery.

CONCLUSIONS

We found that mode of delivery was associated with POP and pelvic floor muscle trauma in women from a general population, 16-24 years after their first delivery. Forceps was associated with significantly more POP, levator avulsion and larger hiatal areas than were vacuum and normal vaginal deliveries. There were no statistically significant differences between vacuum and normal vaginal deliveries. Cesarean delivery was associated with significantly less POP and pelvic floor muscle trauma than were normal or operative vaginal delivery.

Risk assessment for preeclampsia in nulliparous women at 11-13 weeks gestational age: prospective evaluation of two algorithms

OBJECTIVE

To evaluate two algorithms for prediction of preeclampsia in a population of nulliparous women in Norway.

DESIGN

Prospective screening study.

SETTING

National Centre for Fetal Medicine in Trondheim, Norway.

POPULATION

Five hundred and forty-one nulliparous women.

METHODS

The women were examined between 11(+0) and 13(+6) weeks with interviews for maternal characteristics and measurements of mean arterial pressure, uterine artery pulsatility index, pregnancy-associated plasma protein A and placental growth factor. The First Trimester Screening Program version 2.8 by The Fetal Medicine Foundation (FMF) was compared with the Preeclampsia Predictor TM version 1 revision 2 by Perkin Elmer (PREDICTOR).

MAIN OUTCOME MEASURES

Prediction of preeclampsia requiring delivery before 37 weeks, before 42 weeks and late preeclampsia (delivery after 34 weeks).

RESULTS

The performance of the two algorithms was similar, but quite poor, for prediction of preeclampsia requiring delivery before 42 weeks with an area under the curve of 0.77 (0.67-0.87) and sensitivity 40% (95% CI 19.1-63.9) at a fixed 10% false positive rate for FMF and 0.74 (0.63-0.84) and sensitivity 30% (95% CI 11.9-54.3) at a fixed 10% false positive rate for PREDICTOR. The FMF algorithm for preeclampsia requiring delivery <37 weeks had an area under the curve of 0.94 (0.86-1.0) and sensitivity of 80% (95% CI 28.4-99.5) at a 10% fixed false positive rate.

CONCLUSIONS

Fetal Medicine Foundation and PREDICTOR algorithms had similar and only modest performance in predicting preeclampsia. The results indicate that the FMF algorithm is suitable for prediction of preterm preeclampsia.

The effect of exercise and metformin treatment on circulating free DNA in pregnancy

INTRODUCTION

Some pregnancy complications are characterized by increased levels of cell-free fetal (cffDNA) and maternal DNA (cfmDNA), the latter may also be elevated during physical strain. This study aims at assessing the impact of exercise and metformin intervention in pregnancy, and to compare the levels of cell free DNA in pregnant women with or without PCOS diagnosis.

METHODS

Consecutive women from two previous randomized controlled trials in pregnancy were included. Women came from a trial with organized exercise vs. standard antenatal care in pregnancy and a trial of metformin vs. placebo in PCOS women. Levels of cffDNA, cfmDNA and cell-free total DNA (cftDNA) were measured by qPCR.

RESULTS

Training in pregnancy did not affect the levels of cffDNA, cfmDNA or cftDNA. PCOS-women treated with metformin had lower levels of cfmDNA and cftDNA at week 32 (mean ± SD: 301 ± 162 versus 570 ± 337, p = 0.012, 345 ± 173 versus 635 ± 370, p = 0.019); otherwise the levels were comparable to PCOS-controls. Metformin-treated PCOS-women had higher cffDNA at inclusion, in the 1st trimester; later on in pregnancy the levels in the metformin and placebo groups were equal. A comparison of pregnant women in the exercise study (TRIP) to placebo-treated pregnant PCOS-women, showed the levels of cffDNA, cfmDNA or cftDNA during mid-pregnancy (weeks 18-36) to be equal.

DISCUSSION

Training during pregnancy was not associated with altered levels of cffDNA cfmDNA or cftDNA, but metformin treatment may reduce cfmDNA and cftDNA in pregnant PCOS women.

Sonographic prediction of vaginal delivery in prolonged labor: a two-center study

OBJECTIVE

To investigate whether head-perineum distance (HPD) measured by transperineal ultrasound is predictive of vaginal delivery and time remaining in labor in nulliparous women with prolonged first stage of labor and to compare the predictive value with that of angle of progression (AoP).

METHODS

This was a prospective observational study at Stavanger University Hospital, Norway and Addenbrooke's Hospital, Cambridge, UK from January 2012 to April 2013, of nulliparous women with singleton pregnancies with cephalic presentation at term with prolonged first stage of labor. We used transperineal ultrasound to measure HPD (shortest distance between the outer bony limit of the fetal skull and the perineum) and AoP (angle between a line through the long axis of the symphysis and the tangent to the fetal head) and transabdominal ultrasound to classify fetal head position. The main outcomes were vaginal delivery and time remaining in labor.

RESULTS

Of 150 women enrolled, 39 underwent delivery by Cesarean section. The area under the receiver-operating characteristics curve for the prediction of vaginal delivery was 81% (95% CI, 73-89%) using HPD as the test variable and 72% (95% CI, 63-82%) using AoP. HPD was ≤ 40 mm in 84 (56%) women, of whom 77 (92%; 95% CI, 84-96%) delivered vaginally. HPD was > 40 mm in the other 66 (44%) women, of whom 34 (52%; 95% CI, 40-63%) delivered vaginally. AoP was ≥ 110° in 84 of the 145 (58%) in whom this was available and, of these, 74 (88%; 95% CI, 79-93%) delivered vaginally. AoP was < 110° in the other 61 (42%) women, of whom 35 (57%; 95% CI, 45-69%) delivered vaginally. Multivariable logistic regression analysis showed that HPD ≤ 40 mm (odds ratio (OR), 4.92; 95% CI, 1.54-15.80), AoP ≥ 110° (OR, 3.11; 95% CI, 1.01-9.56), non-occiput posterior position (OR, 3.36; 95% CI, 1.24-9.12) and spontaneous onset of labor (OR, 4.44; 95% CI, 1.42-13.89) were independent predictors for vaginal delivery. Both ultrasound methods were predictive for the time remaining in labor.

CONCLUSION

Transperineal ultrasound measurement of HPD and AoP provide important information about the likelihood of vaginal delivery and the time remaining in labor in nulliparous women with prolonged labor.

Comparison between prenatal ultrasound and postmortem findings in fetuses and infants with developmental anomalies

OBJECTIVE

To determine if postmortem examinations of fetuses and infants change the diagnosis obtained at prenatal ultrasound and affect counseling of future pregnancies, and if there has been a change over recent years in the accuracy of prenatal ultrasound diagnosis.

METHODS

This was a retrospective review of 455 autopsies of fetuses and infants with developmental anomalies performed at Trondheim University Hospital between 1995 and 2004 and with a prenatal ultrasound examination performed at a tertiary referral center. The routine ultrasound examinations were performed by specially trained midwives and obstetricians, referral scans by fetal medicine experts and autopsies by consultant pathologists with experience in perinatal pathology. The results of this study were also compared with those of a previous similar study performed between 1985 and 1995, with fetuses and infants coming from the same population and diagnosed at the same center.

RESULTS

Of all cases analyzed during the study period, there was complete agreement between prenatal ultrasound and postmortem findings in 84% (384/455), i.e. prenatal ultrasound diagnoses were supplemented by postmortem examinations in 16% (71/455). Autopsy findings in four of these cases influenced further counseling. There was agreement regarding the main diagnosis in 98% (445/455) of cases. In the previous 10-year period, there was complete agreement in 75% and the main diagnosis was correct in 90% of cases. These differences between the two time periods were statistically significant (P = 0.0004 and P < 0.0001, respectively). The most frequent defects involved the central nervous system, heart and urinary tract. For these defects, detection rates for the main diagnoses were significantly better in 1995-2004 compared with in the previous 10-year period (P = 0.0125, P = 0.0111 and P = 0.0241, respectively).

CONCLUSION

The accuracy of prenatal sonographic detection of developmental anomalies has increased in recent years. However, postmortem examination is still necessary to verify or improve the prenatal diagnosis and may influence future counseling.

Prenatal sonographic assessment and perinatal course of ichthyosis prematurity syndrome

All cases of ichthyosis prematurity syndrome (IPS), registered at the National Center for Fetal Medicine in Trondheim, Norway between 1987 and 2010 were identified and the findings analyzed. Five fetuses with IPS were identified between 1988 and 2000. All five developed polyhydramnios between 28 and 31 weeks. The fetal stomach appeared to be empty in four cases, and was not described in one case. The fetal skin was described as 'uneven' at ultrasound examination in two cases. Separation of chorionic and amniotic membranes with a peculiar appearance of echo-free fluid in the chorionic cavity and echogenic sediment in the amniotic cavity were observed between 28 + 5 and 32 + 3 weeks in all cases. All fetuses were delivered prematurely between 30 and 34 weeks. All neonates had difficulties in breathing, two developed aspiration pneumonia, and one had bilateral pneumothorax after intubation and died at 6 months because of pulmonary and cardiac sequelae. Prenatal sonographic signs of IPS are separation of the membranes, echogenic amniotic fluid and echo-free chorionic fluid occurring between 28 and 32 weeks' gestation. Delivery occurs at 30-34 weeks and, as there is a high risk of asphyxia, an experienced neonatal intensive care unit team should be present at delivery.

Agreement between two- and three-dimensional transperineal ultrasound methods in assessing fetal head descent in the first stage of labor

OBJECTIVE

To study intraobserver repeatability and intermethod agreement between two- (2D) and three-dimensional (3D) transperineal ultrasound methods in assessing fetal head descent during the first stage of labor.

METHODS

Fetal head descent was measured with transperineal ultrasound as the fetal head-perineum distance and the angle of progression in 106 primiparous women with prolonged first stage of labor. A single obstetrician performed all the scans, and another obstetrician analyzed the acquired 2D images and 3D volumes, blinded to clinical assessments and labor outcome. Intraobserver repeatability and intermethod agreement between 2D and 3D methods were analyzed.

RESULTS

The repeatability coefficient was ± 4.1 mm in 2D acquisitions and ± 1.7 mm in 3D acquisitions of fetal head-perineum distance. The intraclass correlation coefficients (ICC) were 0.94 for 2D and 0.99 for 3D measurements. The angle of progression repeatability coefficients were ± 6.7° using 2D and ± 5.7° using 3D ultrasound and ICCs were 0.91 and 0.94, respectively. The intermethod ICC for fetal head-perineum distance in 2D vs 3D acquisitions was 0.95 and for angle of progression it was 0.93; the intermethod 95% limits of agreement were - 5.8 mm to + 7.2 mm and - 8.9° to + 13.7°, respectively. Cohen's kappa for 2D vs 3D acquisitions was 0.85 using 40 mm as a cut-off level for fetal head-perineum distance and 0.79 using 110° as cut-off level for angle of progression.

CONCLUSIONS

For one ultrasound operator the intraobserver repeatability and agreement between 2D and 3D ultrasound methods in prolonged first stage of labor were good. Given that 2D methods are simpler to learn and can be analyzed quickly online, 2D equipment might therefore be preferred in the labor room.

Ultrasound in pregnancy and non-right handedness: meta-analysis of randomized trials

OBJECTIVE

To study the association between exposure to ultrasound in pregnancy and non-right handedness in children with available data from randomized trials.

METHODS

Follow-up data of 8865 children aged 8-14 years from three randomized trials on routine ultrasonography at 15-20 weeks' gestation were available. Handedness was assessed through questionnaires to the parents and classified according to five, 10 or 11 questions. Children not classified as right handed were regarded as non-right handed.

RESULTS

There was a statistically significant increased prevalence of non-right handedness in ultrasonographically screened children compared with controls (odds ratio (OR) 1.15; 95% CI, 1.03-1.29). The results in subgroups according to gender are consistent with the overall results, with no significant differences between boys and girls. Among boys, the association became stronger when an exploratory analysis according to ultrasound exposure before 19-22 weeks' gestation was done (OR 1.30; 95% CI, 1.10-1.53).

CONCLUSION

There is a statistically significant-albeit weak-association between ultrasound screening during pregnancy and being non-right handed later in life.

Prediction of delivery mode with transperineal ultrasound in women with prolonged first stage of labor

OBJECTIVE

To investigate if fetal head-perineum distance and angle of progression measured with two-dimensional (2D) and three-dimensional (3D) transperineal ultrasound could predict outcome of labor in primiparous women with prolonged first stage of labor.

METHODS

This was a prospective observational study of 110 primiparous women with singleton cephalic presentation at term diagnosed with prolonged first stage of labor. Digital assessment of fetal station was related to the ischial spine. Fetal head descent was measured with transperineal ultrasound as the shortest distance from the fetal head to the perineum, and the angle between the pubic symphysis and the fetal head. Receiver-operating characteristics (ROC) curves were constructed and 2D and 3D data acquisitions were compared. The stored 3D volumes were assessed by an examiner blinded to all other data. Vaginal delivery vs. Cesarean section was the primary outcome.

RESULTS

Cesarean section was performed in 25% of the women. Areas under the ROC curves for prediction of vaginal delivery were 81% (95% confidence interval (CI), 71-91%) (P < 0.01) and 76% (95% CI, 66-87%) (P < 0.01) for fetal head-perineum distance and angle of progression, respectively, as measured by 2D ultrasound and 66% (95% CI, 54-79%) for digital assessment of fetal station (P = 0.01). In 50% of women fetal head-perineum distance was ≤ 40 mm and 93% (95% CI, 83-97%) of them delivered vaginally vs. 18% (95% CI, 5-48%) with distance > 50 mm. In 48% of women the angle of progression was ≥ 110° and 87% (95% CI, 75-93%) of them delivered vaginally vs. 38% (95% CI, 21-57%) with angle < 100°. Results from 2D and 3D acquisitions were similar.

CONCLUSION

Fetal head-perineum distance and angle of progression measured with 2D or 3D ultrasound can predict labor outcome, with similar predictive values for the two techniques.

Postpartum onset of rheumatoid arthritis and other chronic arthritides: results from a patient register linked to a medical birth registry

Background:

It is known that onset of rheumatoid arthritis (RA) is increased post partum.

Objective:

To compare incidence rates between RA and other chronic arthritides (OCA) 0–24 months after delivery, and to compare the incidence rates within each group 0–24 versus 25–48 months post partum.

Methods:

Premenopausal women from a Norwegian patient register were linked with the Medical Birth Registry of Norway to study the interval between delivery and time of diagnosis. Cox regression analysis with adjustments for age at delivery and birth order was applied to compare proportions of incident cases of RA and OCA with onset 0–24 months post partum. Poisson regression analysis with adjustment for the population at risk was applied to estimate the incidence rate ratio (IRR) 0–24 versus 25–48 months post partum.

Results:

Of 183 RA and 110 patients with OCA diagnosed after delivery, 69 (37.7%) had RA and 31 (28.2%) OCA during the first 24 months post partum (p = 0.09). The IRR (95% CI) for diagnosis during 0–24 months versus 25–48 months was 1.73 (1.11 to 2.70) (p = 0.01) for RA, 1.05 (0.59 to 1.84) (p = 0.86) for OCA. The IRR was 2.23 (1.06 to 4.70) and 1.87 (0.67 to 5.21), respectively, when only considering diagnoses after the first pregnancy. Clinical characteristics were similar within each diagnostic group.

Conclusion:

The proportions of incident cases with onset 0–24 months after delivery were not different between RA and OCA. A peak in incidence during 0–24 months was seen in the RA group, both when considering all pregnancies and only the first pregnancy.