A yoleddes is in sakanna. Break Shabbos for whatever she needs. It is proper for a woman in her ninth month of pregnancy to prepare before Shabbos to minimize transgressions resulting from a Shabbos birth. (Sha 1 – MB 1)
One of the things that a yoleddes needs is light. Even if she is blind, it calms her to know that people around her can see what to do for her. (ShA 1 – MB 3, 4)
The sakanna status of a yoleddes starts with one of the following indications.:
She sits down on the birthing stool.
Blood begins to flow.
She needs assistance while walking.(ShA 3)
If a woman feels like she might be giving birth imminently, you can call a midwife even before she is in sakanna. (MB 9)
There are three stages of a yoleddes:
Within 72 hours after birth break Shabbos to provide for her anything commonly needed by women after birth. This applies even if she claims that she does not need it. If a doctor or midwife supports her claim, then do not break Shabbos. If Shabbos is the fourth day but 72 hours have not yet passed, you can break Shabbos if no gentile is available. (ShA 4 – MB 10, 11, 12, 13)
From three to seven days after birth – If she says that she does not need the chillul Shabbos, we listen to her unless a doctor or midwife contradicts her. However if she claims that she **needs** the chillul Shabbos, we believe her even against 100 doctors. (ShA 4 0 MB 14)
From seven days until thirty days after birth she has a din of a choleh she’ayn bo sakanna. As stated above in Siman 328 there are three leniencies:
Instruct a goy, even to do a melacha. (MB 16)
Any d’rabbonon employed with a shinui. (ShA 328:17)
Taking medicine. (Rama 328:37)
We are mechallel Shabbos to save the life of an unborn fetus, even when the mother has died. (ShA 5 – MB 18)
Some poskim hold that for an entire 30 days after birth, a woman is in sakanna if she is cold. Try to instruct a goy to make a fire. Actually, this would be allowed for any Jew who is suffering from the cold – he is considered a choleh she’ayn bo sakanna. (ShA 6 – MB 21)