I find the proposed legislation to be very disturbing.
To be fair, I don't think its acceptable to force any healthcare provider to take actions they believe are morally repugnant. In some situations, it does no harm for a doctor/nurse/pharmacist to say 'I don't do ____, but I can refer you to my colleague on the other side of town/the other pharmacist on duty/another doctor in this practice'. Some things are not extremely time sensitive, some people are perfectly capable of being professional and ensuring that patient care is not compromised.
In other situations, health care providers with strong convictions do take actions which are unethical. Like a pharmacist taking a prescription from a customer, refusing to fill it, and then keeping the prescription so that it cannot be filled elsewhere. Or a doctor refusing to treat or refer a patient to another health care provider. Some doctors/nurses have very few choices themselves based upon which hospital employs them (ie Catholic hospitals refusing to dispense drugs (RU 486, IIRC) in the case of ending an ectopic pregnancy and instead surgically removing the affected fallopian tube. Apparently, God is either okay with unnecessary surgery or easily fooled). You can imagine how this would affect medical care in rural areas where there are few choices of medical providers.
Forcing other people to go without appropriate medical care is not a sacrifice. It doesn't matter if if someone disagrees with the morals or actions of the patient, its just wrong. If a person's beliefs are more important than ensuring a patient receives proper care, that person should find another position where they do not have to choose between the two. (That would be a sacrifice, and a choice that demonstrates the value a person places on their beliefs). I don't see why people's jobs should be protected, or hiring practices should be changed to protect that. If anything, the patient should be protected against health care providers who refuse to care for them, or refuse to refer them to someone who will, in a timely fashion.
Its hardly religious discrimination to give someone a list of job requirements and ask 'Are these job requirements something you can do and will feel comfortable performing?'. Its a simple yes or no question, not a matter of beliefs or theology. If the answer is no, sometimes a potential employee can be accommodated and that person should be hired. If they can't be accommodated without compromising medical care, why should they be hired? If a medical practice/hospital must hire in a non discriminatory manner with no eye toward what their employees may or may not refuse to do, where does that end?
And, no, there is no direct proof that the pill causes failure of implantation. If it does occur, it's thought to be a fairly rare occurrence. Orders of magnitude rarer than for women using non hormonal methods of birth control. Even some pro-life Ob/Gyns agree to that.
Hormone Contraceptives: Controversies and Clarifications
As well, women may need the pill to regulate their cycles for IVF (yes, using the pill to try to have kids, and yes, there was a case of a pharmacist refusing to dispense the pill in that situation). Or those with PCOS, fibroids or endometriosis who are trying to preserve their future fertility. Or those with a family history of ovarian cancer trying to reduce their own risk of dying or not being able to have children of their own. Or, women who should not have children due to health reasons. Its a long list, and that does not include the women who simply do not wish to have a child and have chosen a method of birth control that works for them. Really, the 'its possible that this drug may cause a fertilized egg to not implant' warning has been printed on the package insert of every type of oral contraceptive pill I've ever taken. Do people think that women can't read? Can't make decisions for themselves?
When women can't have access to, (or have reduced access) to hormonal birth control, or IUD's, it should be noted that the women lose access to some of the most effective, non permanent methods of controlling their fertility. Its also important to consider the abortion rate and how contraceptive availability influences it.
Recent Trends in Abortion Rates Worldwide
RB-5055: Improvements in Contraception Are Reducing Historically High Abortion Rates in Russia
We're talking about 30% of women in the USA (who use contraception) that use the pill, and having their access to their birth control potentially limited. Ditto for 2 % who use IUDs, 5 % that use Depo-provera. And a lot of people who have another method of birth control fail and would like to use Plan B (another hormonal method of controlling ovulation). This could impact the abortion rate. Not in a good way.