Hello!
4.Whether and how much she is
breastfeeding are the main factors that affect how soon she'll start menstruating again.
But every woman's body and circumstances are different, so there's no reliable way to predict exactly when she'll get her first postpartum period.
If she has been breastfeeding exclusively, day and night, since she had her baby it can take six months or longer.
But the less often your baby nurses, the sooner her period may come back.
2.Intercourse may be started after she have finished her postpartum period about 6 weeks.
3.She can put IUD right after childbirth ,or in any time .
4.There are many methods for birth control like condoms ,pills,devices(diaphragma,caps) ect.
All the best