Maternal herpes labialis in pregnancy and neural tube defects

Maternal genitourinary infections and risk of birth defects in the National Birth Defects Prevention Study

BACKGROUND

Genitourinary infections (GUIs) are common among sexually active women. Yet, little is known about the risk of birth defects associated with GUIs.

METHODS

Using data from the National Birth Defects Prevention Study, a multisite, population-based, case-control study, we assessed self-reported maternal GUIs in the month before through the third month of pregnancy (periconception) from 29,316 birth defect cases and 11,545 unaffected controls. We calculated odds ratios (ORs) and 95% confidence intervals to estimate the risk of 52 major structural birth defects associated with GUIs. We also calculated risk of birth defects associated with each type of GUI: urinary tract infection (UTI) and sexually transmitted infection (STI).

RESULTS

In our analysis, 10% (n = 2,972) of case and 9% (n = 1,014) of control mothers reported a periconceptional GUI. A GUI was significantly associated with 11 of the 52 birth defects examined (ORs ranging from 1.19 to 2.26): encephalocele, cataracts, cleft lip, esophageal atresia, duodenal atresia/stenosis, small intestinal atresia/stenosis, colonic atresia/stenosis, transverse limb deficiency, conoventricular septal defect, atrioventricular septal defect, and secundum atrial septal defect. A periconceptional UTI was significantly associated with nine birth defects (ORs from 1.21 to 2.48), and periconceptional STI was significantly associated with four birth defects (ORs ranging from 1.63 to 3.72).

CONCLUSIONS

While misclassification of GUIs in our analysis is likely, our findings suggest GUIs during the periconceptional period may increase the risk for specific birth defects.

Maternal genitourinary infections and the risk of gastroschisis

Genitourinary infections (GUIs) have been associated with increased risk of gastroschisis in 2 studies. Using data collected in the Slone Epidemiology Center Birth Defects Study, we examined the association between GUI and gastroschisis. From 1998 to 2010, mothers of 249 gastroschisis cases and 7,104 controls were interviewed within 6 months of delivery about pregnancy events, including vaginal infections, genital herpes, urinary tract infections (UTIs), and other sexually transmitted diseases (STDs). Women were considered exposed if they reported at least 1 instance of a GUI in the first trimester. Logistic regression models were used to calculate odds ratios and 95% confidence intervals. Women who reported having any GUI had an adjusted odds ratio of 1.8 (95% confidence interval (CI): 1.3, 2.4). The highest risk was seen among women who reported a UTI only (adjusted odds ratio = 2.3, 95% CI: 1.5, 3.5), while the odds ratio for an STD only was slightly elevated (adjusted odds ratio = 1.2, 95% CI: 1.0, 1.5). Among women under 25 years of age, the odds ratio for UTI only was 2.6 (95% CI: 1.7, 4.0), and among older women it was 1.8 (95% CI: 0.6, 5.9). When we considered the joint association of UTIs and young maternal age, a synergistic effect was observed. The results of this study add further evidence that UTIs may increase the risk of gastroschisis.

Maternal self-reported genital tract infections during pregnancy and the risk of selected birth defects

BACKGROUND

Genital tract infections are common during pregnancy and can result in adverse outcomes including preterm birth and neonatal infection. This hypothesis-generating study examined whether these infections are associated with selected birth defects.

METHODS

We conducted a case-control study of 5913 children identified as controls and 12,158 cases with birth defects from the National Birth Defects Prevention Study (1997-2004). Maternal interviews provided data on genital tract infections that occurred from one month before pregnancy through the end of the first trimester. Infections were either grouped together as a single overall exposure or were considered as a subgroup that included chlamydia/gonorrhea/pelvic inflammatory disease. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression with adjustment for potential confounders.

RESULTS

Genital tract infections were associated with bilateral renal agenesis/hypoplasia (OR, 2.89; 95% CI, 1.11-7.50), cleft lip with or without cleft palate (OR, 1.46; 95% CI, 1.03-2.06), and transverse limb deficiency (OR, 1.84; 95% CI, 1.04-3.26). Chlamydia/gonorrhea/pelvic inflammatory disease was associated with cleft lip only (OR, 2.81; 95% CI, 1.39-5.69). These findings were not statistically significant after adjustment for multiple comparisons.

CONCLUSIONS

Caution is needed in interpreting these findings due to the possible misclassification of infection, the limited sample size that constrained consideration of the effects of treatment, and the possibility of chance associations. Although these data do not provide strong evidence for an association between genital tract infections and birth defects, additional research on the possible effects of these relatively common infections is needed.

Spatial analysis of neural tube defects in a rural coal mining area

Shanxi province in northern China has one of the highest reported prevalence rates of neural tube defects (NTDs) in the world. The current study selected Heshun, the county with the highest rate of NTDs in Shanxi, as a study area and tested whether residence in a coal mining area was a contributing factor. A NTD cluster was detected in an area within 6 km of the coal mines for almost every year during 1998-2005. Poisson regression analysis revealed that there may be an association between production in coal mines and prevalence of NTDs in coal mine areas. Future work identifying factors independently correlated with NTDs in coal mining regions may provide further insights into the health effects of coal mines on NTDs.

Case-control study of self reported genitourinary infections and risk of gastroschisis: findings from the national birth defects prevention study, 1997-2003

OBJECTIVE

To assess the association between genitourinary infections in the month before conception to the end of the first trimesterand gastroschisis.

DESIGN

Case-control study with self reported infections from a computer assisted telephone interview.

SETTING

National birth defects prevention study, a multisite, population based study including 10 surveillance systems for birth defects in the United States.

PARTICIPANTS

Mothers of 505 offspring with gastroschisis and 4924 healthy liveborn infants as controls.

MAIN OUTCOME MEASURE

Adjusted odds ratios for gastroschisis with 95% confidence intervals.

RESULTS

About 16% (n=81) of case mothers and 9% (n=425) of control mothers reported a genitourinary infection in the relevant time period; 4% (n=21) and 2% (n=98) reported a sexually transmitted infection and 13% (n=67) and 7% (n=338) reported a urinary tract infection, respectively. Case mothers aged <25 years reported higher rates of urinary tract infection alone and in combination with a sexually transmitted infection compared with control mothers. In women who reported both types of infection, there was a greater risk of gastroschisis in offspring (adjusted odds ratio 4.0, 95% confidence interval 1.4 to 11.6).

CONCLUSION

There is a significant association between self reported urinary tract infection plus sexually transmitted infection just before conception and in early pregnancy and gastroschisis.