A thyroid that’s too slow (hypothyroidism) can throw a wrench in your reproductive plans, and you might not even be aware that this butterfly-shaped gland’s speed is out of control.
Symptoms of having an underactive thyroid include constipation, heavier periods, weight gain, a decrease in appetite, fatigue, and depression. Hypothyroidism can prevent ovulation by raising prolactin levels (a hormone involved in producing breast milk). It can also bring on a condition known as luteal phase defect, making it impossible for the body to build up a uterine lining to accept a fertilized egg. Simple blood tests can diagnose the condition, and taking synthetic thyroid hormones can set the speed to normal—and fertility.