How does obesity affect pregnancy planning?
Most experts advise that obese women should try to attain a normal body mass index before conception, although a preconception weight loss intervention has never been tested in a clinical trial. As nearly half of all pregnancies in the US are unplanned, routine medical visits in all women of reproductive age may be viewed as opportunities to discuss preconception planning, including weight loss among overweight and obese women. Effective contraception should be offered to women who want to delay pregnancy while trying to lose weight. Obesity may affect efficacy of contraception, and among women using contraception obese women are more likely to have an unintended pregnancy, although the reasons are unclear.7 Although some studies have found an association between obesity and failure of oral contraception, others have not confirmed this relation.8 Additionally, contraceptives that contain oestrogen may be contraindicated in some obese women with hypertension and/or diabetes.
