Effects of testosterone on rat placental development

Area of Science:

• Reproductive biology
• Developmental toxicology
• Endocrinology

Background:

• Polycystic ovarian syndrome (PCOS) is linked to hormonal imbalances, including elevated androgens.
• Maternal androgen excess during pregnancy may affect fetal development and placental function.
• Understanding these effects is crucial for managing pregnancy complications in women with PCOS.

Purpose of the Study:

• To investigate the impact of testosterone administration on placental morphology and development in a rat model of PCOS.
• To determine the timing and nature of placental changes induced by testosterone exposure.

Main Methods:

• Pregnant rats were administered testosterone propionate (TP) from gestation day (GD) 14 to GD 18.
• Maternal and fetal parameters, including weight and intrauterine growth retardation (IUGR) rates, were assessed.
• Placental histology and morphology were examined at GD 15, 17, and 21.

Main Results:

• TP administration led to maternal weight reduction but no mortality.
• A significant decrease in fetal and placental weight and increased IUGR rates were observed on GD 21.
• Histological analysis on GD 21 revealed thickened trophoblast septa and narrowed maternal sinusoids in the labyrinth zone, consistent with placental underdevelopment.
• These placental changes on GD 21 mirrored those observed on GD 17, suggesting developmental inhibition from GD 17 onwards.

Conclusions:

• Maternal testosterone excess in a PCOS rat model inhibits placental development, primarily affecting the fetal component from GD 17 onwards.
• This inhibition results in smaller placentas and contributes to intrauterine growth retardation.
• The findings highlight the potential adverse effects of androgen excess on pregnancy outcomes.