This is an unorganized accumulation of various thoughts.
Maybe helpful would be to focus on the "responsible drinker card", even though this is more than that.
But to begin, a bit about my philosophy about this.
Generally, a mother is the most important and valuable person for the child and deserves full respect and authority. Within reason.
Mothers with mental difficulties, and other situations can be an exception.
The father shares responsibility, and similar treatment, but is always under the mother's reign.
The parent's responsibility is their own, and as long as upheld, "private ownership" of a child is acceptable.
However, it is the responsibility of every capable adult, and society as a whole to protect each and every child.
Intrusion by government agencies generally is a bigger problem than the problem it intends to solve.
Because of the "private ownership" of children (in almost all societies), it is difficult for society to know the true quality and status of a child's life. Then to intervene is complicated by the individual rights of the parents, even when their parental rights are reduced or removed.
Although the rest of the text here is focused on alcohol, it can apply similarly to other drugs, with appropriate adjustments. And applies to misuse of prescription drugs.
It is up to society to prevent it's children from being subjected to poisoning by alcohol, nicotine, heroine, and the rest.
This means that each individual and group, working within and outside of government, needs to prevent any pregnant woman from consuming anything possibly harmful to the baby. Society has a right to intervene as necessary to protect the baby.
But the point is that every sales point, or other person or group providing alcohol (or ...), insures that it will not be accessible by pregnant women or underage drinkers. Directly and when further distributed.
This can be done with laws, contracts, whatever, but of course will probably be ineffective for alcohol, nicotine, or ..., addicts.
I feel morally and should be legally, every person at every point in a delivery chain of such substances is guilty of severe child abuse, and should be punished as such for each case of a baby receiving a dosage of such a substance.
The acknowledged/proven father should be held to the same strict standards as the mother, where fits.
The mother as soon as found to have ingested, she needs to be incarcerated in reasonably home like surroundings until the child is born. Immediately losing the child to society for placement elsewhere. To prevent another occurrence, imprisonment until no longer fertile. Of course free sterilization is available.
This idea and many others I have really only if sterilization is free and readily available for everyone, especially at young ages. A voluntary sterilization, paid or free, is always entitled to a free reversal at a later date. A small verification process is maybe okay, but I expect more people will be willing do this if they are guaranteed a reversal.
The original name thought of for this is "responsible drinker card" (RDC), but something else that obviously includes all drugs would be clearly be better.
The basic idea is a photo ID card that a person can present at a store or a bar to verify they agreed to be responsible with the substance(s), and including knowing they are not pregnant, as well as not further providing to underage persons, etc.. The agreement is also that unsure if pregnant means no usage as well.
Sales and distribution points can record the data of purchases, and get a significant discount. This encourages usage of the card. The discount can be reimbursed by the government, or possibly in combination with suppliers however that might not work out well.
Basically to get the RDC, the person would take lessons, probably best a number spread over time, interview, etc. and whatever, to have a reasonable assurance the person understands the risks, options, responsibilities, penalties, how to get help, etc.
The person signs or states in a video agreeing to not provide or allow access to underage persons, and especially possibly pregnant women. The agreement can further include provisions to allow inspections in vehicles and residences, maybe. The user insures having tested for pregnancy as appropriate before consumption.