@Tom Brady @ExGingi is a insurance broker, and I have bought travel insurance from him in the past. He is probably your best resource on these forums.
Based on personal experience,
do not travel without TI that covers pregnancy, especially so late in pregnancyA relative of mine traveled from IL to the US for a wedding in about week 21, and the night before the return flight she had some complications that ruled out flying before birth (there was even concern for viability of the child). She had forgoten to do insurance...
B"h As she was a US citizen, she managed to get on medicare, which is covering her ongoing hospitalisaition... but all the other expenses, that would normaly get paid for by travel insurance, are now out of pocket.
Unless you are willing to make aliya to get bituach leumi...
Anyway, Bsha'ah Tova.