The main thing to look for in reinitiating physical intimacy after birth is whether or not you have stopped bleeding. If you have- it shouldn't be an issue. My hubby and I made it to 3 weeks, then waited another week or so--and this has been my best post partum recovery by far!
Are you asking because you feel that this has impeded your healing in some way?
It is not a myth that breastfeeding causes ammenoreah. It really does suppress ovulation...however how long it suppresses ovulation varies from woman to woman depending on many factors-- whether or not the baby is getting any artificial nipples, how strong baby's suck is, whether or not baby is nursing throughout the night, the space between feedings-and just genetics.
If you are contemplating chemical contraception- be aware that it can have very detrimental effects on your milk supply.