Pathways linking socioeconomic status to small-for-gestational-age (SGA) infants among primiparae: a birth cohort study in China

The Effects of Ying Yang Bao on Nutritional Status of Children Aged 6-60 Months in Underdeveloped Rural Areas of China

The Ying Yang Bao (YYB) intervention, a national policy in China, has been implemented for over two decades. Most previous studies have focused only on the short-term effects of YYB, while the long-term effects remain unexplored. This study was designed to evaluate the long-term effects of YYB in children aged 6-60 months. A sample of 4666 children was divided into intervention and control groups. Information on basic characteristics, physical examination, YYB consumption, etc., was obtained annually from 2018 to 2021. T-tests or chi-square tests were used to compare differences between the groups for continuous or categorical variables. Children in the intervention group showed greater incremental improvements in hemoglobin levels and physical development (p < 0.05). Prevalence of anemia, underweight, and stunting were lower in the intervention group than in the control group (all p < 0.05). Two-level regression models were constructed to assess the long-term effects of YYB. YYB reduced the risk of anemia and wasting by 37% (OR: 0.63, 95% CI: 0.52-0.75) and 49% (OR: 0.51, 95% CI: 0.39-0.67), respectively. This study indicates that YYB could significantly improve the nutritional status of children aged 6-60 months in underdeveloped rural areas of China.

Mediating role of birth at a baby-friendly hospital in the association between parental socioeconomic status and infant exclusive breastfeeding at six months old

BACKGROUND

Current evidence suggests that the exclusive breastfeeding (EBF) rate at six months postpartum in China falls considerably below the targets recommended by the World Health Organization (WHO). Socioeconomic disparities in EBF have been observed in developing countries, with significant heterogeneity across studies. Despite the implementation of the Baby-Friendly Hospital Initiative (BFHI) in China since the 1990s to promote breastfeeding, there has been a lack of assessment concerning infants from different socioeconomic backgrounds. This study sought to investigate the association between socioeconomic status (SES) and EBF and explore the potential impact of giving birth at a Baby-Friendly Hospital (BFH) on this association.

METHODS

We analyzed data from 98,469 mother-child dyads selected from the Maternal and Child Health Management Information System. We used log-binomial models to examine the relationships between SES and EBF, SES and giving birth at a BFH, as well as BFH births and EBF. Additionally, we explored a counterfactual mediation approach to assess the mediating role of BFH births in the SES-EBF association.

FINDINGS

We identified a significant association between SES and EBF (RRMedium vs. Low = 1.47, 95% CI 1.39-1.55; RRHigh vs. Low = 1.40, 95% CI 1.32-1.49). Mothers with higher SES were more likely to give birth at BFHs (RRMedium vs. Low = 1.85, 95% CI 1.81-1.88; RRHigh vs. Low=2.29, 95% CI 2.25-2.33). The significance of the SES-EBF association was attenuated when the type of hospital for childbirth was considered, revealing the significant mediating effect of BFH births in the SES-EBF association.

CONCLUSION

Socioeconomic disparities are linked to infant EBF rates, with giving birth at a BFH mediating this association, especially for cases with low SES in rural areas.

Socioeconomic Factors and Abortive Outcomes of Clinical Pregnancy After Embryo Transfer in the Setting of Universal Health Insurance Coverage of IVF

BACKGROUND

In vitro fertilization-embryo transfer (IVF-ET), an expensive option for infertile couples, started to be fully covered by the National Health Insurance (NHI) from October 2017 in South Korea. We investigated the association between woman's socioeconomic status (SES) and abortive outcomes in pregnancies after IVF-ET in the setting of universal coverage of the treatment.

METHODS

Using the NHI database in South Korea, we conducted a retrospective cohort study of all women who achieved clinical pregnancy after ET between October 2017 and February 2019. A total of 44,038 clinical pregnancy episodes of 29,847 women who underwent ET were analyzed. We used employment status, income in percentiles, and living in the Seoul capital area as indicators of SES. Relative risks (RRs) for abortive pregnancy outcomes were calculated for each socioeconomic stratum, using log-binomial regression models included woman's age, body mass index, fasting blood glucose, fresh ET, month of ET, and history of smoking.

RESULTS

While most pregnancy outcomes were live births (n = 30,783, 69.9%), 11,215 (25.5%) cycles ended with abortion or early pregnancy loss, 1,779 (4.0%) cycles were ectopic pregnancy, 45 (0.1%) were coded as molar pregnancy, and 224 (0.5%) were fetal death in utero or stillbirth. The risk of overall abortive outcomes was higher when a woman was unemployed (adjusted RR, 1.08; 95% confidence interval [CI], 1.05-1.11) or living in a non-Seoul capital area (1.11; 95% CI, 1.08-1.14). The association between relative income level and abortive outcomes was close to null. Living outside Seoul capital area was associated with the greater risk of abortive outcomes especially in younger women.

CONCLUSION

Unemployment and living in non-capital areas were associated with a higher risk of abortive outcomes among pregnancies after ET, even in the setting of universal coverage of IVF-ET. This suggests potential impact of socioeconomic position on the IVF-ET pregnancy.

Impact of Maternal Monocyte to High-density Lipoprotein Cholesterol Ratio on the Incidence of Large-for-gestational-age Newborns: An Observational Cohort Study

BACKGROUND AND OBJECTIVES

Monocyte to high-density lipoprotein cholesterol ratio (MHR) has recently been identified as a new marker of inflammation and oxidative stress. However, it is unknown whether maternal MHR is associated with fetal weight at birth. Therefore, our objective was to analyze the association between maternal MHR and the frequency of small/large for gestational age (SGA/LGA) newborns in this retrospective cohort study.

METHODS

We retrospectively analyzed hospitalization records and laboratory data and obtained results from consecutive pregnant women in whom the blood lipid level had been investigated along with the blood cell count. Linear regression and logistic regression analyses were performed to estimate the associations of maternal MHR with birth weight and SGA/LGA.

RESULTS

Monocyte counts and MHR were positively associated with birth weight/LGA risk (monocyte [1-109/L increase] for birth weight: β: 170.24, 95% confidence interval [CI]: 41.72-298.76, LGA: odds ratio [OR]: 7.67; 95% CI: 2.56-22.98; MHR [1-109/mmol increase] for birth weight: β: 294.84, 95% CI: 170.23-419.44, LGA: OR: 7.97; 95% CI: 3.06-20.70), whereas high-density lipoprotein cholesterol (HDL-C) levels were negatively associated with birth weight/LGA risk [1 mmol/L increase for birth weight (β: -99.83, 95% CI: -130.47 to -69.19), for LGA: (OR: 0.57, 95% CI: 0.45-0.73). Obese pregnant women (body mass index [BMI] ≥30 kg/m2) with higher MHR (tertile 3: >0.33 109/mmol) significantly increased LGA risk by 6.39 fold (95% CI: 4.81, 8.49) compared to those with low MHR (tertile 1-2: ≤0.33 109/mmol) and normal weight (BMI <25 kg/m2).

CONCLUSION

Maternal MHR is associated with LGA risk, and this association might be further modified by BMI.

International Consensus Guideline on Small for Gestational Age (SGA): Etiology and Management from Infancy to Early Adulthood

This International Consensus Guideline was developed by experts in the field of SGA of 10 pediatric endocrine societies worldwide. A consensus meeting was held and 1300 articles formed the basis for discussions. All experts voted about the strengths of the recommendations. The guideline gives new and clinically relevant insights into the etiology of short stature after SGA birth, including novel knowledge about (epi)genetic causes. Besides, it presents long-term consequences of SGA birth and new treatment options, including treatment with gonadotropin-releasing hormone agonist (GnRHa) in addition to growth hormone (GH) treatment, and the metabolic and cardiovascular health of young adults born SGA after cessation of childhood-GH-treatment in comparison with appropriate control groups. To diagnose SGA, accurate anthropometry and use of national growth charts are recommended. Follow-up in early life is warranted and neurodevelopment evaluation in those at risk. Excessive postnatal weight gain should be avoided, as this is associated with an unfavorable cardio-metabolic health profile in adulthood. Children born SGA with persistent short stature < -2.5 SDS at age 2 years or < -2 SDS at age of 3-4 years, should be referred for diagnostic work-up. In case of dysmorphic features, major malformations, microcephaly, developmental delay, intellectual disability and/or signs of skeletal dysplasia, genetic testing should be considered. Treatment with 0.033-0.067 mg GH/kg/day is recommended in case of persistent short stature at age of 3-4 years. Adding GnRHa treatment could be considered when short adult height is expected at pubertal onset. All young adults born SGA require counseling to adopt a healthy lifestyle.

Association of maternity formula supplementation during pregnancy with small for gestational age birth in Chinese newborns

OBJECTIVES

This study aimed to explore the association between maternity formula supplementation and small for gestational age (SGA) status in Chinese newborns.

METHODS

Data were from a population-based cross-sectional survey conducted in Shaanxi, Northwest China between August and December 2013. A total of 27 780 women pregnant with singletons and 356 with twins were included in this survey. Information on use of maternity formulas fortified with vitamins, folic acid, pantothenic acid, calcium, iron, zinc, and docosahexaenoic acid (DHA) was collected. SGA was defined as birthweight <10th percentile of fetal growth. Generalized linear models and estimating equation models were used to estimate crude odds ratios (ORs) or adjusted ORs with 95% confidence intervals (CIs) for SGA.

RESULTS

The rate of maternity formula supplementation during the entire pregnancy was 13.0% in the overall population. There was no significant association between maternal formula supplementation during pregnancy and the risk of total SGA birth (OR: 1.00; 95% CI, 0.90-1.11; P = 0.950). However, maternity formula supplementation during pregnancy was related to a lower risk of SGA for twins (OR: 0.49; 95% CI, 0.31-0.80; P = 0.004), twin A (OR: 0.50; 95% CI, 0.25-0.98; P = 0.045), and twin B (OR: 0.48; 95% CI, 0.25-0.95; P = 0.034). Furthermore, maternity formula supplementation during the first trimester was inversely associated with the risk of SGA birth of twins (OR: 0.32; 95% CI, 0.15-0.65; P = 0.002).

CONCLUSIONS

No significant association was observed between maternity formula supplementation and total SGA birth. However, women supplemented with maternal formula during pregnancy, especially during the first trimester, may have a reduced risk of SGA birth of twins.

Neurodevelopmental toxicity induced by airborne particulate matter

Airborne particulate matter (PM), the primary component associated with health risks in air pollution, can negatively impact human health. Studies have shown that PM can enter the brain by inhalation, but data on the exact quantity of particles that reach the brain are unknown. Particulate matter exposure can result in neurotoxicity. Exposure to PM poses a greater health risk to infants and children because their nervous systems are not fully developed. This review paper highlights the association between PM and neurodevelopmental toxicity (NDT). Exposure to PM can induce oxidative stress and inflammation, potentially resulting in blood-brain barrier damage and increased susceptibility to development of neurodevelopmental disorders (NDD), such as autism spectrum disorders and attention deficit disorders. In addition, human and animal exposure to PM can induce microglia activation and epigenetic alterations and alter the neurotransmitter levels, which may increase risks for development of NDD. However, the systematic comparisons of the effects of PM on NDD at different ages of exposure are deficient. The elucidation of PM exposure risks and NDT in children during the early developmental stages are of great importance. The synthesis of current research may help to identify markers and mechanisms of PM-induced neurodevelopmental toxicity, allowing for the development of strategies to prevent permanent damage of developing brain.

Effects of the Duration of Ying Yang Bao Consumption on Hemoglobin Concentration in Infants and Young Children in Less Developed Areas of China

Ying Yang Bao (YYB) is conventionally prescribed as a nutritional supplement to infants and young children (IYC) in less developed areas of China. However, whether 18-month YYB consumption is reasonable needs assessment. This study examined the influence of the duration of YYB consumption on hemoglobin (Hb) levels and anemia prevalence. Data from the Nutrition Improvement Project on Children in Poor Areas of China in 2018-2019 were used. Questionnaires were used to collect information on basic characteristics, dietary status, and YYB consumption. Propensity score matching (PSM) was used to balance confounders. Hb levels and anemia prevalence in IYC with different durations of YYB consumption were compared. After PSM, all covariates were well-balanced, and 1151 pairs of IYC were included in subsequent analyses. During the 1st-9th months of intervention, YYB effectively increased Hb levels and reduced anemia prevalence in the intervention group. During the 10th-18th months of intervention, Hb levels in the control group increased and anemia prevalence decreased, while Hb levels and anemia prevalence fluctuated in the intervention group. In conclusion, YYB was effective in improving nutritional status of infants, but had a limited effect in young children. Nutritional supplements with different quantities or nutrients should be considered for young children.

Promoter methylation changes in the placenta involved in the relationship between prenatal depression and small for gestational age

BACKGROUND

Recent studies suggest that the incidence of small for gestational age (SGA) birth related to maternal depression, but the mechanism is unclear. The aim of this study was to explore the changes of promoter methylation in the placenta which may be involved in the relationship between prenatal depression and SGA.

METHODS

Three hundred forty-five pregnant women were enrolled in this prospective cohort study. Perinatal emotion and sleep quality in the second and third trimesters were assessed using self-rating depression scale, self-rating anxiety scale, and Pittsburgh sleep quality index. According to the exposure (depressed emotion of mother) and outcome (SGA), the placentas were divided into four groups. Methylation of the promoter regions of the placental CRH, HSD11β2, SLA16A10, DIO3, and MTNR1B genes was determined using next generation sequencing based on bisulfite sequencing PCR.

RESULTS

There were 97 (28.1%) and 95 (27.5%) pregnant women who had depression in the second trimester and third trimester, respectively. Thirty-five pregnant women had an SGA birth. The incidence of SGA births in this prospective cohort was 10.1%. The risk factors of SGA birth were low BMI of pregnancy women (RR = 0.71, 95%CI = 0.54 ~ 0.92), hypertensive disorder complicating pregnancy (HDCP, RR = 4.7, 95%CI = 1.18 ~ 18.72), and maternal depression in the second trimester (RR = 3.71, 95%CI = 1.31 ~ 12.16). We found that the CRH and HSD11β2 methylation levels were higher in the depression group than those in the non-depression group. Methylation levels of DIO3 were higher in SGA group than that in the non-SGA group. Higher methylation levels of CRH correlated with higher methylation levels of DIO3 in the placenta.

CONCLUSIONS

Maternal depression in the second trimester may lead to the changes of methylation levels in the promoter region of CRH and HSD11β2 gene, while the changes of methylation of DIO3 in subsequent could related to SGA. This study suggests that maternal depressed emotion during pregnancy may result in SGA due to the epigenetic changes of placenta.

Demographic, socio-economic, obstetric, and behavioral factors associated with small-and large-for-gestational-age from a prospective, population-based pregnancy cohort in rural Nepal: a secondary data analysis

BACKGROUND

In South Asia, a third of babies are born small-for-gestational age (SGA). The risk factors are well described in the literature, but many studies are in high-and-middle income countries or measure SGA on facility births only. There are fewer studies that describe the prevalence of risk factors for large-for-gestational age (LGA) in low-income countries. We aim to describe the factors associated with SGA and LGA in a population-based cohort of pregnant women in rural Nepal.

METHODS

This is a secondary data analysis of community-based trial on neonatal oil massage (22,545 women contributing 39,479 pregnancies). Demographic, socio-economic status (SES), medical/obstetric history, and timing of last menstruation were collected at enrollment. Vital signs, illness symptoms, and antenatal care (ANC) attendance were collected throughout the pregnancy and neonatal weight was measured for live births. We conducted multivariate analysis using multinomial, multilevel logistic regression, reporting the odds ratio (OR) with 95% confidence intervals (CIs). Outcomes were SGA, LGA compared to appropriate-for-gestational age (AGA) and were multiply imputed using birthweight recalibrated to time at delivery.

RESULTS

SGA was associated with nulligravida (OR: 2.12 95% CI: 1.93-2.34), gravida/nulliparous (OR: 1.86, 95% CI: 1.26-2.74), interpregnancy intervals less than 18 months (OR: 1.16, 95% CI: 1.07-1.27), and poor appetite/vomiting in the second trimester, (OR: 1.27, 95% CI: 1.19-1.35). Greater wealth (OR: 0.78, 95% CI: 0.69-0.88), swelling of hands/face in the third trimester (OR: 0.81, 95% CI: 0.69-0.94) parity greater than five (OR: 0.77, 95% CI: 0.65-0.92), male fetal sex (OR: 0.91, 95% CI: 0.86-0.98), and increased weight gain (OR: 0.93 per weight kilogram difference between 2^nd and 3^rd trimester, 95% CI: 0.92-0.95) were protective for SGA. Four or more ANC visits (OR: 0.53, 95% CI: 0.41-0.68) and respiratory symptoms in the third trimester (OR: 0.67, 95% CI: 0.54-0.84) were negatively associated with LGA, and maternal age < 18 years (OR: 1.39, 95% CI: 1.03-1.87) and respiratory symptoms in the second trimester (OR: 1.27, 95% CI: 1.07-1.51) were positively associated with LGA.

CONCLUSIONS

Our findings are in line with known risk factors for SGA. Because the prevalence and mortality risk of LGA babies is low in this population, it is likely LGA status does not indicate underlaying illness. Improved and equitable access to high quality antenatal care, monitoring for appropriate gestational weight gain and increased monitoring of women with high-risk pregnancies may reduce prevalence and improve outcomes of SGA babies.

TRIAL REGISTRATION

The study used in this secondary data analysis was registered at Clinicaltrials.gov NCT01177111.

Pediatric respiratory hospitalizations in small for gestational age neonates born at term

OBJECTIVE

This study investigates the risk for long-term respiratory hospitalizations of offspring born small for gestational age (SGA) at term.

STUDY DESIGN

A retrospective population-based cohort analysis was performed to examine the risk of long-term respiratory hospitalizations between SGA compared to appropriate for gestational age (AGA) newborns. The analysis included all term singleton deliveries occurring between 1991 and 2014 at a single tertiary medical center. Fetuses with congenital malformations, multiple gestation, cases of perinatal mortality and large for gestational age (LGA) were excluded. A Kaplan-Meier survival curve was used to compare cumulative morbidity incidence up to the age of 18 years, and a Cox hazards regression model was used to control for confounders.

RESULTS

During the study period 216,671 deliveries met the inclusion criteria; of them 4.8% (n = 10,450) were diagnosed as SGA neonates. During the follow-up period, the rate of hospitalization due to respiratory morbidity was significantly higher in the SGA group as compared to the AGA group (5.2% vs. 4.7%, OR = 1.13, 95% confidence interval [CI] = 1.03-1.24, p = 0.011). The Kaplan-Meier survival curve demonstrated a significantly higher cumulative incidence of respiratory morbidity in the SGA group (log-rank p = 0.026). In the Cox hazards regression model, controlled for relevant clinical confounders, SGA was found to be an independent risk factor for long-term pediatric respiratory morbidity (adjusted hazard ratio [HR] = 1.1, 95% CI = 1.001-1.19, p = 0.049).

CONCLUSION

Being delivered SGA at term is an independent long-term risk factor for pediatric respiratory hospitalization.

Association and potential mediators between socioeconomic status and childhood overweight/obesity

The associations between socioeconomic status and childhood overweight/obesity are inconsistent, and potential underlying factors are unclear. In China, Hukou status is an important attribute of individual's socioeconomic circumstances, but previously received less consideration as a socioeconomic indicator. This study aimed to investigate the association between comprehensive socioeconomic status and childhood overweight/obesity. Using data from Wuhan Maternal and Child Health Management Information System (2009-2018, N = 209,500), clustering analysis was used to create comprehensive socioeconomic groups with indicator components such as parental education level, occupation, and maternal Hukou. The associations between the determined socioeconomic status and childhood overweight/obesity at age 1 and 2 were examined by log-binomial model. Parallel and serial mediation analyses were performed to test the indirect effects of potential mediators, including maternal pre-pregnancy body mass index, gestational weight gain, and infant birth weight, in the association between socioeconomic status and childhood overweight/obesity. Four clusters, defined as low, low-medium, medium-high, and high socioeconomic groups, were identified through clustering analysis. Hukou, among five socioeconomic components, contributed the most to the development of childhood overweight/obesity. Children in the low-medium socioeconomic group have a greater risk of overweight/obesity than the low socioeconomic group. Indirect effects of maternal pre-pregnancy body mass index, gestational weight gain, and infant birth weight were identified for the association. In conclusion, socioeconomic status may impact childhood obesity through maternal pre-pregnancy body mass index, gestational weight gain, and infant birth weight. Hukou should be considered in the evaluation of socioeconomic status in China.

The independent and combined influences of small for gestational age and socioeconomic status on newborn metabolite levels

OBJECTIVES

To determine whether socioeconomic status (SES) and small birthweight for gestational age (SGA) exhibit independent or joint effects on infant levels of 42 metabolites.

STUDY DESIGN

Population-based retrospective cohort of metabolic newborn screening information linked to hospital discharge data. SGA infants defined by birthweight <10th percentile for gestational age by sex. SES was determined by a combined metric including education level, participation in the WIC nutritional assistance program, and receiving California MediCal insurance. We performed linear regression to determine the effects of SES independently, SGA independently, and the interaction of SGA and SES on 42 newborn metabolite levels.

RESULTS

736,435 California infants born in 2005-2011 were included in the analysis. SGA was significantly associated with 36 metabolites. SES was significantly associated with 41 of 42 metabolites. Thirty-eight metabolites exhibited a dose-response relationship between SGA and metabolite levels as SES worsened. Fourteen metabolites showed significant interaction between SES and SGA. Eight metabolites showed significant individual and joint effects of SES and SGA: alanine, glycine, free carnitine, C-3DC, C-5DC, C-16:1, C-18:1, and C-18:2.

CONCLUSIONS

SES and SGA exhibited independent effects on a majority of metabolites and joint effects on select metabolites. A better understanding of how SES and SGA status are related to infant metabolites may help identify maternal and newborn interventions that can lead to better outcomes for infants born SGA.

Pregnancy outcomes of Chinese women undergoing IVF with embryonic cryopreservation as compared to natural conception

Background

To examine differences in the maternal characteristics and pregnancy outcomes of Chinese women with various causes of infertility who underwent in vitro fertilization (IVF) with embryonic cryopreservation treatment.

Methods

Cases were pregnancies after IVF-ET with embryonic cryopreservation; controls were spontaneously conceived pregnancies. Subgroup analysis was carried out according to etiology of infertility. The IVF treatment group was divided into 5 subgroups according to infertility etiology as follows: ovulation disorder, tubal disease, male infertility, endometriosis, and mixed infertility. Data on demographic characteristics, medical history, laboratory tests, and delivery were reviewed. Logistic regression analysis was performed for pregnancy and perinatal complications and neonatal outcomes. The multivariable model was adjusted for potential confounders.

Results

Among singleton pregnancies, compared with spontaneous pregnancies, IVF pregnancies were associated with significant increases in the rates of the following: gestational diabetes mellitus (GDM) (aOR 1.76[95% CI 1.33–2.33]), preeclampsia (2.60[1.61–4.20]), preterm preeclampsia (4.52[2.03–10.06]), postpartum hemorrhage (1.57[1.04–2.36]), intrahepatic cholestasis of pregnancy (3.84[1.06–13.94]), preterm premature rupture of membranes (2.11[1.17–3.81]), preterm birth (1.95[CI 1.26–3.01]), low birthweight (1.90[1.13–3.20]), macrosomia (1.53[1.03–2.27]), and neonatal intensive care unit (NICU) admission (1.69[1.22–2.34]) in the ovulation disorder group; GDM (1.50[1.21–1.86]), placenta previa (2.70[1.59–4.59]), placenta accreta (1.78[1.10–2.89]), postpartum hemorrhage (1.61[1.19–2.18]), macrosomia (1.60[1.21–2.13]) and 5-min Apgar score ≤ 7 (4.09[1.04–16.08]) in the tubal disease group; placenta previa (9.33[4.22–20.62]), small for gestational age (2.29[1.04–5.08]), macrosomia (2.00[1.02–3.95]) and NICU admission (2.35[1.35–4.09]) in the endometriosis group; placenta previa (4.14[2.23–7.68]) and placenta accreta (2.05[1.08–3.87]) in the male infertility group; and GDM (1.85[1.15–2.98]), placenta previa (4.73[1.83–12.21]), placental abruption (3.39[1.20–9.56]), chorioamnionitis (2.93[1.04–8.26]), preterm birth (2.69[1.41–5.15]), and 1-min Apgar score ≤ 7 (4.68[1.62–13.51]) in the mixed infertility group. Among multiple pregnancies, most of the differences that were significant in singleton pregnancies were less extensive or had disappeared.

Conclusions

Infertility etiology within the IVF population was found to affect maternal and neonatal outcomes among all births. During the perinatal period, infertility etiology appears to be an additional risk factor for abnormal pregnancy outcomes besides the use of IVF techniques compared with spontaneous pregnancies. Higher risk was found for ovulation disorders, and lower risk was found for male infertility.