ReviewCurrent knowledge of obesity's effects in the pre- and periconceptional periods and avenues for future research
Section snippets
Obesity and ovulation
Increased incidence of subfertility among obese women may be attributed in part to the frequent cooccurrence of obesity with polycystic ovary syndrome (PCOS),20 a relatively common condition characterized by hyperandrogenism and anovulation and associated with insulin resistance.21, 22 PCOS is not uncommon in women of normal weight; however, in obese women insulin resistance may lead to clinical features consistent with PCOS.23, 24
Insulin resistance and hyperinsulinemia consequent of obesity
Obesity and the oocyte
Insight into the importance of maternal physiology on oocyte quality can be demonstrated in experimental animal models of maternal diabetes in which there is an increase in granulosa cell apoptosis of the ovarian follicle and impaired oocyte maturation.15, 16, 38 Similar to diabetes, obesity is a condition marked by aberrations in circulating levels of substrates for energy production, and it too appears to have effects on oocyte quality. Visually, these effects appear to be primarily on oocyte
Obesity and the embryo
Embryo quality is affected by poor oocyte quality, and this may be an issue for obese women. This has been documented clinically in obese women undergoing IVF in which embryos derived from oocytes fertilized in vitro are of poorer quality than those derived from normal-weight women.48, 57 On the other hand, IVF studies investigating embryo quality in obese women are conflicting, and their findings on embryo quality may not reflect what truly happens in spontaneous conceptions.58
Another issue to
Obesity and early pregnancy
In addition to increased risks of congenital anomalies, preeclampsia, gestational diabetes, and stillbirth among obese pregnant women,8, 9, 66, 67, 68 there are also data to suggest risk of miscarriage is increased among obese women.69 This association is difficult to study, however, because many spontaneously pregnant women are not followed up closely in early pregnancy and may not ever present for care if they experience a miscarriage. Women undergoing infertility treatment may offer more
Limitations of current evidence and future avenues for research
The bulk of the current data available investigating relationships between obesity and oocytes and early reproduction in spontaneous conception is restricted to work in animal models and a small amount of clinical data from obese women undergoing IVF (Table 2). Unfortunately, the available clinical data are limited in that most women undergoing IVF are treated with gonadotropins. Drug regimens and protocols and response to drugs may vary from patient to patient, with many obese women requiring
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Cited by (145)
Neighborhood disadvantage is associated with decreased ovarian reserve in women with overweight and obesity
2023, Fertility and SterilityMetabolic risk factors and fertility disorders: A narrative review of the female perspective
2022, Reproductive Biomedicine and Society OnlinePolycystic Ovary Syndrome and Irritable Bowel Syndrome: Is There a Common Pathway?
2024, Endocrinology, Diabetes and MetabolismPreconception Diet Interventions in Obese Outbred Mice and the Impact on Female Offspring Metabolic Health and Oocyte Quality
2024, International Journal of Molecular SciencesObesity and Miscarriage
2024, Seminars in Reproductive Medicine
E.S.J. receives support through the Women's Reproductive Health Research Career Development Program of the National Institutes of Health (K12HD063086-01).
Reprints not available from the authors.